Telephone call transmitter



1 March 4, c R D TELEPHONE CALL TRANSMITTER Filed Nov. 28, 1944 eSheets-Shea 1 m w w w By CLZR/CHARD I ATTORNEY 4, 19 c. D. RICHARD2,416,715

TELEPHONE CALL TRANSMIT-TER Filed Nov. 28, 1944 6 SheetsSheet 2 INVENTQRC. D. RICHARD ATTORNEY March 1947' v c. D. RICHARD 2,416,715

I I TELEPHONE CALL TRANSMITTER Filed Nov. 28, 1944 6 Sheets-Sheet 3 c 0.RICHARD A TTORNE V I Mamh 4 .c. D. RICHARD I 2,416,715

TELEPHONE CALL TRANSMITTER 1 Filed Nov. 28, 1944 s Sheets-Sheet 4 FIG. 7

FIG. 8

IN VENT'OR c.0. R/CHA RD 5;? wma A TTORNEV March 7- c. D. RICHARD ITELEPHONE CALL TRANSMIT'P Filed Nov. 28, 144

6 Sheets-Sheet 5 INVENTOR By C D RICHARD ATTORNEK l atented Mar. 4, 1947Charles D. Richard, West New Brighton, N. Y., as-

signor to Bell Telephone Laboratories, Incorporated, New York, N. Y., acorporation of New York Application November 28, 1944, Serial No.565,459

21 Claims. (01. 179-90) This invention relates to telephone calltransmitters and more particularly to call transmitters oi thekey-operated type.

The object of the invention is to provide a call transmitter of the typeabove referred to which will be simple in construction, convenient touse, and positive in operation,

A feature of the invention is the provision of a set of key members foroperating a, pivoted bar and causing the operation of means operativelyassociated with the keys for controllingthe operation of motor meansgeared to a pulsing mech anism.

Another feature is the provision of means in the form of a step bar andgear sector unit movable concentric to the pivoted bar by the operationof the motor for actuating the pulsing mechanism, means in the form ofan operable stop being provided for normally holding the step bar gearvsector. unit and the pulsing V mechanism geared thereto from operationduring the movement of the pivoted bar under control of the operated keymember.

Another feature is the provision of means carried by the pivoted bar'for operating the stop means and a pawl bar movable therewith for per:mitting the operation of the step bar gear sector unit and locking the'non-operated keys collectively in that position upon the operation ofone of the key members. e

- Another feature is the provision of means carried by the key memberseffective to cause the operation of spring-pressed pawls for lockingtheir individually associated keys inthe operated position during theoperation of the step bar gear sector unit and that of the pulsingmechanism geared to the motor.

Another feature is the provision of camming means carried by the pivotedbar 'forimparting a longitudinal movement to a shaft for moving acontact spring actuating member in position effective relative to a camin the pulsing mecha nism for actuating such a contact spring upon theoperation of the step bar gear sector unit as effected by the motor.

Another feature is the provision of means carried' by the spring-pressedpawlsfor engaging their respective steps in the step bar gear sectorunit for controlling the angular movement of such unit and thereby theoperation of the pulsing cam in relation to the digit value of thedepressed key. I

Another feature is the provision of spring means tensioned against oneend of the shaft supporting the contactspring actuating element forreturning such element in position non-effective relative to the pulsingcam during the return movement of the latter and the step bar gearsector unit to normal position for avoiding noise.

. 2 7 Another feature is the provisionof means carried by. thespring-pressed pawls engaged by their respective steps in the step bargear sector unit for releasing the operated key following the operationof the pulsing mechanism.

Another feature is the provision of a motion amplifiermechanism foractuating a wedging device serving to prevent th reoperation of any one:ofthe keys prior to the return movement of that key to full normalunoperated position.

Another feature is the provision of means operable for engaging thepivoted bar and thereby looking all the keys in normal non-operatedposition following the placing of the telephone handset'in a cradleformed with the casing housing the transmitter mechanism, thuspreventing manipulation of the keys when the telephone is notin use. A ZOther novel features and advantages of this invention will appear fromthe following description andv by the claims appended thereto, referencebeing had to the accompanying drawing in which: v V

Fig; l is a perspective view of the call transmitter of this inventionembodied in a, so.-called telephone desk set, the keys being shown innormal position and the telephone handset in position in a cradle formedwiththe casing housing the transmitter mechanism;

2 is a perspective view of the call transmitter of thisinventionembodied in a soecalled telephone coin collectonbox;

Fig. 3 is a right side elevation view showing the casing partly invertical longitudinal section showing the motion amplifier mechanism andthe keys'in normal position;

Fig; '4 is a view'similar .to that of Fig. 3 but showing the motionamplifier mechanism and one of'th'e keys in' the operated position;

Fig. 5 is a left side elevation view partly in vertical longitudinalsection showing the pulsing mechanism and the keys in normal position;

Fig; 6 is an elevation view shown partly in ver tical section taken online 6-6 of Fig. 8, the keys being shown in normal position; I r

Fig. 7 is a plan view partly in horizontal section taken on line 'I---'!of Fig. 9;

Fig. '8 is a rear elevation view tions taken'on line 8--8 of Fig. 3;

Fig. 9 is a vertical longitudinal sectional View taken on line 99 ofFig. '7 showing the step bar and the keys in normal position; Y 7

Fig. 10 is a view similar to that of Fig. 9 but showing one of thekeys'and the step :bar in operated position; v

FigsQll and 12 are views of amodification of the step bar and gearsector unit and the key locking mechanism in different operatedpositions: g Fig, 13 is a detailview showing the collective shown inseckey locking mechanismein the operated position; Fig. 14 is a partialplanview showing'a modi fied drive for the pulsing mechanism;

Fig. 15 is a partial elevation view shown in ver- Fig. 14, the" ticalsection taken on line l--i5 of keys being in normal position; a Fig. 16is a partial rear view of Fig. 14;

Fig. 17 is a partial View showing one ofthe keys v and its locking pawlin normal non-operated posi tion holding the motor contact associatedwith that key inthe open position; and

Fig. 18 is a diagrammatic viewer .the. motor energizing circuit.

Referring togthe drawings, a base it is pro- V vided for securin as by anumber of similar screws it the upright supports I l and 15. These 1supports as best seen 'in'Figfs. 6-, 8, '9 and 'lo are held inspacedrelation to each other attheir lower and upper ends by parallellydisposed plates I I and l8having registering rectangularly-shapedopenings as shown in Fig. 7 serving as guides for a by retractingsprings 19, constructed in the form of a comb secured between the baseBand a metallic strip 2B under the tightening efiect of a number ofscrews 21, while a strip'22 of non-metallic material secured to theunderside of plate I8 serves for damping the movement of the keys 1 whenthe latter are returned to normal position 1 under the tension of theirrespective springs it 1 following their release from operatedpositionlin a manner which will be hereinafter described in detail." 7 vIA U-shaped bar 23 best seen in Figs. 7 and 8 has its parallel arms 23Aand 23B pivoted on a shaft 24 journaled in supports 25 and 26 secured 1set oflongitudinally movable key members Kl, 1' K2, K3, K5, K5, K6, K1,K8, K9 and Kill. These keys are yieldably held in non-operated'positionto the base I3 as by a' plurality of similar screws 27. The bar 23extends transverse-of thefkey members Kl, K2, Ka'etc}. in openingsformed. in

hereinafter described in detail.

; The upright support l5, as best seen in Figs. 3

ande, is provided with aprojection 29 for pivotally mounting as on ashoulder screw 29Y a lever member 30. This lever is providedat itsmiddle length portion with an oblong-shaped opening 3! engaged by aroller 32 mounted ona pin 33 supported at one end by the arm 23B of Ushaped bar 23 and a projection 38Y formedwith that arm. I i' J The freeend of arm is provided with an 013-.-

long-shaped opening 34 for. receiving a roller 35: Y carried by a levermember 36. The lever 36, as

best seen in Fig. 7, terminates in a U-shaped bend providing bearingsfor pivoting this arm on the shaft 24,'the arm 37 thus formed having anupward extending lug portion 38 provided for hookin one end of the motorspring 28 while the opposite end of this spring is hooked to 9. lug 39formed with a gear sector 40 pivoted on shaft 25 and forming an arm of astep bar ti of arcuate 1 cross-section best seen in Figs. 7, 8, 9 and10.

The plate M in turn is formed integrally with an arm 42Y bent at rightangles thereto and piv- 1 oted at its end on shaft 24. This plate issecured to the gear sector 40 through lugs LI and L2 fengagingsimilarly-shaped openings in the gear secthese keys for operation by theindividual move- 7 j ment of the latter from normal to operated posij Jtion as shown by key K5 'in'Fig. 10, the operation '1 of bar 23 beingeffective totension a motor spring 23 and to perform other functionsWhich will be 1 tor 4H for riveting or weldingand steps as S|,- S2. S3,S4, S5; 86,31. S8, S9 and Sill are provided 4 7 at the edge of the platto perform functions which Will-be hereinafter described in detail.

" The 'U-shaped bar 23 and the step bar s! thus constructed are normallycollectively held in the non-operated position as shown in Figs. 3, 5,6, 8

and 9 by the tension of a rectractile spring 43 hooked at one end to thedownwardly extending projection 32X of lever so and its opposite end toa lug MH formed with an element of a'wedging device in the form of a barsecured to the upright supporti 5 as by a number of screws 451 i the arm3! formed with lever 35 being provided and 9, carried by alever member46 secured to this bar as by welding, engages the undersurface or'edg'eof plate ii at the point adjacent its arm @282 for preventing theoperation of this bar during the movemen of the U-shaped bar 23 fortensioning the motor spring 23. The bar 4! is moved in position forengaging a ridge rd formed at right angles therewith withthe teeth asshown in Figs. 9 and 10 formed with the keys for locking thenon-operated keys in that position simultaneously. with the disengagingof lu 54 from the stepbar gear sector unit thus formed for permittingthe operation of such a unit and thereby the operation of, a pulsingmechanism which will be hereinafter described in detail.

The movement of bar 4? for locking the nonoperated key in timed relationwith the release of the step bar ii upon the operation of anyone of thekeys is effected by the engagement of a cam portion 52 formed with thearm 23B of U- shaped bar 23 with a roller R mounted at the free end ofarm it, while a two-way spring 53 secured to the cam portion 52 normallyholds the lever 46'fO110Wing the movement of bar 23 in a positionwherein the lug 54 carried thereby is clear of the step bar 3 i.

A plurality of pawl-like members :56, one for each key member Kl, K2,etc; are pivoted on a common shaft 51 extending in slots SL2 formed inthe keys as shown'in'Figs. 9 and 10. These pawls are'actuat'ed-bysimilar spring 58 following the movement of their respective keys 1 fromnormal to operated position for individually locking these keys to theposition indicated by key K5 for'example in Fig. 10 wherein the pawl 56associated with that key-under control of the cam surface CA engages thetooth or shoulder portion 51 for locking its associated key in theoperating P0$ition In the movement of pawl 55 as for locking itsassociated key is eiTectiye to position its cam surface C5 and its stopT5 in'engageable relationwith the corresponding step S5 in the step barii, preparatory to the operation of this bar, the functionoflp'rojection S5, as in this example, being to engage the cammingportion C5 of the operated pawl 56 for disengaging the operated keyfollowing the operation of the step bar gear sector unit and that of thepulsingmechanism at an angular distance corresponding to the digit valueof the depressed key, while the function of stop T5 of this pawllikemember is to stop the movement of the step lhe bar 52 is normally heldin 8, engages a pinion 66 keyed on a shaft 6| supported at one end byupright support 48 and its opposite end by a bracket 62 secured to theupright M by screws 63. On shaft 6| is keyed a pulsing cam 64 having ahub portion 65 of a diameter corresponding to the diameter of a hub 66formed with a worm gear 61 mounted for free rotation on shaft 6|, thiswormgear being operatively connected to impulse cam 64 by a clutchspring 66 coiled on the hub of worm gear 61 and the hub 65 of impulsecam 64 to operate as a one-way clutch between the worm gear and theimpulse cam for driving a centrifugal governor mechanism CG through theengagement of the Worm gear 61 with a worm 69 on the governor shaft.

The upright support i4 is provided with an opening OP, best seen in Fig.5, permitting the assembly of pulsing cam 64, worm gear 61, pinion 66and clutch spring 68 and shaft 6| as a unit prior to the mounting ofthis shaft in position in its bearings in support 48 and bracket 62.

The upright support I4 is formed with two bracket elements 16 and H,best seen in Figs. 5, '7 and 8, having bearing portions for a shaft 12mounted for angular and longitudinal movement, and on this shaft iskeyed an angle lever I3 having one of its arms positioned inengageablerelation with the pulsing cam 64 through the engagement of a ribbonspring 5| having its free end fitted for sliding movement in a slotformed in the projection of a plate 5|X serving to secure thecooperating springs of a contact 16 in a pile-up assembly on the uprightsupport l4 and the other arm 13 of this angle lever being provided witha stud 14 of insulating material disposed in engageable relation withthe operable spring 15 of the pulsing contact 16.

A spring 11 bent upon itself, asbest seen in Fig. 8, has one of its endssecured to the bracket H and its opposite end tensioned against one endof shaft 12 for resiliently and normally holding this shaft and theangle lever 13 keyed thereon in position out of engagement from theimpulse cam 6-4, while a cam 18 carried by the arm 23A of the U-shapedbar 23 is provided for engaging the opposite end of'shaft 12 forimparting a longitudinal movement to this shaft, when the bar 23reachesa small angular distance from its full operated position as effected byany one of the key members KI, K2, K3, etc., for

placing the angle lever 73 in operative relation with the impulse cam 64for operating the pulsing contact 16 during the movement of this cam inthe direction indicated by the arrow shown in Fig. 5, as effected by theoperation of the gear sector 49 under the tension of motor spring 28 andthereby actuating the operable spring 15 of pulsing contact 16, theextent of the angular movement of gear sector 46 as above describedbeing controlled by the step bar 4| engaging any one of pawl-likemembers 56 which may be operated by the movement of its respectivelyassociated key. 3

A U-shaped lever Ll of the wedging mechanism is mounted, as best seen inFigs. 3 and 4, for longitudinal and pivotal movement on a stud STlaterally extending from the upright sup-, port |5. This lever isprovided with a roller 19 normally held against the'stop bar by apivoted-camming element 86 underthe tension of a spring Pl havingnormally it line of tension above the center of stud P2 on which thiscamming element is supported. The angular movement of camming element 86in its upward direction is limited by a stop in the form of a lug L2formed with the bar 45 while the'downward movement of this camming armis. limited by a lug L3 also formed with the bar 45. g

The pivotal movement of camming element 86 from the position shown inFig. 3 to the position shown in Fig.4 is effected by the engagement of apin BUY carried by the wedge portion 11 of lever 36 with the arm AI ofthis camming element upon the operation of any one of the keys andconsequently the operation of bar 23, the levers 36 and 36. The movementof camming element .86 as above described causes the line of tension ofspring P1 .to pass the dead center of pivot P2 and thereby cause thisspring to yieldably hold the cam element 86 in the position shown inFig. i so as to permit the pivotal movement of lever L| for positioningthe roller 19 carried thereby between the bar 45 and the wedge portionT4 of lever 36 at the time the operated key and therefore lever 36 reachtheir full operated position.

Upon the release of the key K5 in the example above mentioned, and theconsequent return movement of arm 36 to normal position, i. e., from theposition shown in Fig. 4 to the position shown in Fig. 3, the arm 36 isfree to return to its normal non-operated position without, interferencefrom the roller 19 now engaged with the wedge portion TI of this leverand with the bar 45. Under this condition, however, an attempt by anoperator to return the, key to operated position, prior to its fullreturn to normal non-operated position, causes the downward movement ofarm 36, which, in turn, causes the wedge portion Ti to force the roller19 against the bar 45 so as to prevent any downward movement of the key.

In the modification shown in Figs. 11 and 12,

position for locking their respective keys by similar springs X2. Eachpawl 96 is provided with an arm 96 extending in engageabl relation withtheir respective steps in thestep bar 4|, while lever members as 9 2 arepivoted on a shaft 93 for movement in engageable relation with the stepsSI, S2, S3, etc., of their respectively associated pawls 96 through theengagement of pins 94 in slots formed in the pawls 96,.the lever members92 having lug portions 95 bent at right angles thereto to form stops forthe arms 96, formed with pawls 96 for holding the latter in operativerelation with their respective steps formed with bar 4| when theirrespective keys are moved to the locked positions, while lugs, such as91, formed with the lever members 92, serve for stopping the movement ofthe step bar 4| so as to limit the movement of the gear sector 46movable therewith to angular distances which correspond to the digit ofthe key depressed, the movement of pawl 96 from the position shown inFig. 12 to the position shown in Fig. 11 as effected by the engagementof step bar 4| with arm 96 ofpawl 96 being effective to release theoperated keywhich is then returned to normal position by the tension ofits own retracting spring l9.

As shown in Fig. 13, a mechanism is provided whereby the manualoperation of key members KI, K2, K3, etc., is prevented when thetelephone .is .notin use through the engagement ofthe U,

shaped bar 23 by a pawl I pivoted on a lever member IIH. This leverislactuated by one of .the plunger members I52 engaging with a camsurface 1 as at the free end of this lever upon the placingof thetelephone handset in position in r a cradle formed with the casing CXhousing the transmitter mechanism. The :pawl H19 is resiliently held .inengageable relation with the U-bar 23 by a retractile spring I04normally urging this pawl against a stop carried by lever NH, the

spring I54 permitting the movement of the pawl as effected upon thereturn movement of the U- transmitter of this invention, the downwardmovement of any one of the key members, as .key K5 :in the exampleabove-mentioned, from the position shown in Fig. 9 to the position shownin Figs. 4 and 10, is effective to impart a pivotal movement to theU-shaped bar 23 and thereby a pivotal movement to levers 30 and 36 fortensioning the motor spring 28, while the roller I9 of the wedgingmechanism is held in the position shown in Fig. 3 by the camming arm 85under the tension of spring Pl, the line of tension of which is nowabove the dead center of pivot P2 supporting the camming arm,

The gear sector 40 and the stop bar 4| movable therewith are held in thenon-operated position, as shown in Figs. 8 and 9, by the stop lug 54 ofarm 46 so as to prevent the operation of this step bar gear sector unitand that of the pulsing mechanism during the tensioning of the motorspring as effected by the manual operation of key member K5above-mentioned. Movement of U.- shaped bar 23 but a small angulardistance from its full operatedposition causes the cam '52,:car-

ried by arm 23B of U-shaped bar 23, to engage latter from the positionshown in Fig. 31to the position shown in Fig. 4, thus releasing theroller i9 which falls as by gravity between the wedge l1 and the bar 45.

The movement of arm 46 so as to releasethe step bar gear sector unitcauses the bar 4'! secured thereto to move in the position shown in Fig.10 in the path of teeth of keys KI, K2, K3, K4, K6, K1, K8, K5 and KlEl, thus locking these keys in the non-operated position, the two-way.retractile spring 53 now holding the bar 41 in the operated positionwith the lug '54 of .arm'46 out of iristional contact with the arcuateedge of arm lZY formed with the step bar 4!, while the locking of theoperated key K5 is effected as above-described by the operation ofspring-pressed pawllike member 5% having its lug portion 55 engaging theshoulder portion 51 of key K5 in timed relation with the release of stepbar gear sector unit and the operation of camming arm 80 for movementfrom the position shown in Fig.3 to the position shown in Fig. 4. I

The movement of spring-pressed pawl member 56 for locking its operatedkey K5 also positions its camming surface 05in the path of theprojectionformed withthe stepS5 of the step bar to be actuated by themovement of the latter for releasing the operated key K5 following theoperation of the pulsing mechanism as effected by the gear sector 40.bar 23 by key K5 through its cam EB, best seen in Figs. 5, 6, 7 and 8,is effective to impart a longitudinal movement to the shaft 12 againstthetension of its retractile spring 11 and thereby positioning the anglelever 73 .in operative relation with the pulsing cam 64 which occurssimultaneously with the release of the step bar 41 by the operation ofarm 46. The operation of the step bar and the gear sector 40 isefiective to actuate the pinion 60, the shaft BI and thereby the impulsecam .54 in the direction indicated by the arrow in Fig. 5. The pulsingcam now clutched to the worm gearfi'l rotates under control of the gov.-ernor mechanism CG for operating the angielever 13 and thereby thespring 15 for opening the contact '15 a number of times corresponding tothe angular movement of gear sector 50 from nor- ,mal to the pointwherein the projection formed with step S5 moves its associated pawlmember 56 against the tension of its .retractile spring 58 fordisengaging the lug "55 of this pawl from the shoulder portion of key K5which is then returned to normal position by the tension of itsretractile spring I9.

Upon the return movement of key K5 to normal and consequently the returnmovement of the 'U-shaped bar 23, the cam '18 carried by arm 23A of thibar is effective to free the shaft 72 which is returned to normalposition by the tension of its retractile spring 17 so as to prevent theoperation of the latter duringthe rotation of impulse cam 54 in thedirection opposite to that indicated by the arrow in Fig. 5, and therebypreventing noises from this source.

The return movement of the U-shaped bar 23 through the engagement of lug55A with the arm 42Y of the step bar 41, and the connection of arm 35with the arm .35 to which the retractile spring 43 is attached, thewedge portion T? of lever 35 is free to move in the directionindicated'by the arrow in Fig. 4 without interference from roller to.press the key K5, prior to its return to full normal position, causesthe wedge TI to move the roller downward forcing the latter against thebar 45 resulting in locking the keyagainst an downward movement. Uponthe return of key K5 buta smaller angular distance from normalnonoperated position, the pin carried by the wedge portion l'i engagesthe underside of cammingarmiBll for pivoting the latter from the position shown in Fig. 4 to the position shown in Fig. 3, where the line oftension of sprin PI is moved above the center of pivot P2 for yieldablyholding thi camming arm and roller it in the non-operated position, thusagain permitting the operation of anyone of the keys.

The return movement of U-shaped bar23 and the step .bar gear sector unitto normal position, the free end of retractile spring 53, is effectiveto return the lever 46 to normal position, and thereby positioning thelug 54 carried by that lever in'reengagement with the step bar 4! whilepositioning the bar 47 out of the path-of teeth 50 of the keys and thetransmitter is now ready for theoperation of a succeeding key for theoperation of the pulsing mechanism as described in connection with theoperation of key K5.-

The placing, of the telephone handset HS in its cradle; which is. formedwith casing CXin Fig. 1, the operation of plunger I02, as shown in Fig.13,

The operation of U-shaped- However, an attempt by the operator to deiseffective to impart a small angular movement to the lever IOI againstthe tension of its retractile spring I08 for placing the pawl I inengagement with the underside of U bar 23 and thereby preventing themanipulation of any one of the keys when the telephone handset is not inuse. In cases when the handset is placed inits cradle prior to thereturn of the depressed key, in normal non-operated position, the returnmovement of the U-shaped bar 23 by the tension of the retractile springI64 causes the pivotal movement of pawl I00 to a point wherein the pawlis free to.

move under the lower edge of bar 23 for locking the keys in the mannerabove-described.

In the operation of the transmitter of this invention by the use of themodified mechanismv shown in Figs. 11 and 12, the operation of key K inthe example above-described, the spring X2 respective to that key causesthe engagement of pawl 90 with the shoulder portion SP for holding thatkey in the operated position, as shown in Fig. 12. The angular movementof pawl 90 for locking its associated key is effective to position itsarm portion it in engageable relation with the step S5 of step bar 4|.Such movement, however, is limited by a stop in the form of lug 95formed with the arm 92 pivoted on shaft 93, while the pivotal movementof pawl 90 is effective to move the arm 92 for positioning the lug 9'!formed with that arm in the path of step S5 of step bar M for stoppingthe movement of the latter as eifected by the tension of motor spring 28following the engagement of step bar 4| with arm 96 and the consequentpivotal movement of pawl 90 so as to disengage its operated key as shownin Fig. 11 to permit the return movement of the latter to normalposition under the tension of its own retractile spring [9, which isfollowed by the return movement of U-shaped bar 23 to normal position asabove-described, while the continued pivotal movement of pawl 90 undercontrol of the cam portion I00 formed with that key is effective to movethis pawl to an angular distance suiiicient to position the free end ofarm 96 away from frictional contact with the step bar 4| and themechanism is now ready for the operation of a succeeding key.

In the modification shown in Figs. 14, 15, 16, 17 and 18 the worm gear61 and the magnetic clutch H0 secured thereto are mounted for freerotation on shaft 6|. This magnetic clutch is provided with slip ringsIH, H2 engaged by brushes H3 and H4 securely mounted on a lug H5 formedwith the support 48. The magnetic clutch H0 is disposed in attractablerelation with a pulsing cam 64 keyed on one end of shaft 6|, to theother end of which is secured a pinion 5t meshing with the gear sector40 of the step bar gear sector unit. r

The Worm gear 54 meshes with a worm 69 keyed on or formed with a shaft H6 journaled in bearing portions H1 and H8 formed with support 43 whileon the opposite end of shaft H 5 i keyed a worm gear H9 meshing with aworm l 2!! keyed on the armature shaft of a motor M, in circuit with themagnetic clutch H0 through the brushes H3 and H4 and normally opencontacts Tl, T2, T3, T4, T5, T5, T1, T8, T9 and TI!) closed by theoperation of pawl-like members 53 best seen in Fig. 17 under control oftheir respectively associated key members Kl, K2, K3, etc., as will behereinafter described in detail.

Contacts Tl, T2, T3, etc., as best seen in Fig. 17

are formed in the manner of combs and mounted in an inverted pile-uparrangement to the under 10' side of a spacer bar l2l secured at bothends to lugs I22 formed with the upright supports l4 and I5 by a numberof similar screws I23, the spacer bar serving as support for the motorM.

In a typical example of operation by the use of the electric motor drivemechanism of this invention the operation of key K5 as in the exampleabove-mentioned is effective to impart an angular movementto theU-shaped bar 23 for actuating the arm 46 to engage the ridge rdof bar 41with the tooth 50 of each non-operated key while disengaging the lug 54carried by lever 46 from the bar 4| and simultaneously causes themovement of pawl-like member 56 under the tension of the operable springI24 of contact T5. to close its contact andlock the key in the operatedposition. In that condition the motor and the magnetic clutch areenergized through a circuit comprising the conductor W, see Fig. 18,connecting to one side of the telephone line, the now closed contact T5,the conductor WI, connecting with the motor M, the wires W2, the brushH4, the slip ring H2, the coil of the magnetic clutch, not shown, theslip ring III, the brush H3 and the conducting wire W3 connecting withthe other side of the telephone line. The rotation of the motor andthereby that of the now energized magnetic clutch is effectiveto attractits armature which is formed with the pulsing cam 64 for rotating thelatter and thereby the pinion 60 in mesh with the gear sector 40 of thestep bar gear sector unit for actuating the latter to a point whereinstep S5 of the step bar engages the camming surface S5 of pawl-likemember 65 for operating the latter for releasing the operated key andreopening the contacts T5 tocause the deenergization of the magneticclutch, and stopping the operation of the motor. The operated key isreturned to normal non-operated position by the tension of itsretractile spring l9 followed by the return of the U-shaped bar 23 tonormal nonoperated position by the tension of retractile spring 43 inthe manner described in the example of the operation in connection withthe mechanism shown in Figs. 2, 3, 4, 5, 6, '7 and 8 and the transmitteris again ready for the operation of a succeeding key and while the motorM is described as being operatively connected to the telephone line, itis obvious, that, it may be connected to any electric source instead.

What isclaimed is:

1. A call transmitter comprising a set of key' members, a step bar andgear sector unit, a pulsing mechanism geared to the sector of said'unit,

a motor, means actuated by the operation of'one ment of any one of saidkey members, a gear sector, a step bar arranged for movement with saidgear sector as a unit, a motor for actuating said unit, a movable stopelement normally holding said unit from operation during the operationof said pivoted bar, means carried by said pivoted bar for actuatingsaid stop means to cause the operation of said unit, and a pulsingmechanism actuated by said gear sector.

3. In a call transmitter, a set of longitudinally the movement of saidbar for actuating said gear 1 sector, a step bar secured to said gearsector for movement therewith as a unit, means engaging said step barfor holding said unit against movement during the tensioning of saidmotor spring by the operation of said bar, a, cam carried by said barfor actuating said operable means following the. tensioning of saidmotor spring for releasing said unit, a pulsing mechanism actuated bysaid gear sector, means positioned by the movement of the operated keycooperating with one of the steps in said step bar for controlling theoperation of said pulsing mechanism, means for returning the operatedkey to normal following the operation of said pulsing mechanism, andmeans for returning said bar and said unit to normal simultaneously vwith the return of the operated key to normal.

4. In a call transmitter, a set of longitudinally movable key members, amounting having means for guiding said key members, a shaft supportedlevers and its opposite end connected to said unit,

means for holding said unit from operation upon the tensioning of saidmotor spring by the movement of said pivoted bar, means actuated by saidpivoted bar for actuating said holding means to cause the operation ofsaid unit, a pulsing mechanism actuated by the gear sector of said unit,and means set .by the operated key member actuated by the step bar ofsaid unit for controlling the extent of operation of said pulsingmechanism for transmitting a number of pulses correspondin'g'to theoperated key member.

5/ In a call transmitter, a set of key members, a shaft, a bar mountedfor free movement on said shaft and actuated by the operation of any oneof Said key members, a step bar and ear sector unit mounted for freerotation on said shaft, movable means normally positioned in the path ofsaid unit, a pulsing mechanism operais;

tively connected to the gear sector of said unit. a motor springtensioned by the movement of said bar relative to said unit foractuating said mechanism, means carried by said bar for actua ing saidmovable means to cause the operation of said pulsing mechanism by thegear sector of said unit, a pawl cooperating with means carried by thedepressed key for locking the latter to operated position,said pawlhaving means engaged by the step bar of said unit under the tension ofsaid motor spring for unlocking the operated key following the operationof said pulsing mechanism, spring means for returning the operated keyto normal position, and'spring means actuating said unit, a camoperatively connected to the gear sector of said unit, a pulsingcontact, a pawl-like member for actuating said pulsing contact normallyin position out of engageable relation from said cam, said bar havingmeans for moving said pawl-likemember in the path of said cam foroperating said contact'upon the operation of said unit by said motor,operable means ifor holding said unit from movement during the pendentlyactuating means for returning the op erated key, said bar and said unitto normal following the operation of said pulsing mechanism, and springmeans for returning said pawl-like member out of engaged relation fromsaid cam upon the return of said pivoted bar to normal.

'7. A call transmitter comprising a set of key members, a movable stepbar and gear sector unit, a motor for actuating said unit, combined stopand latch elements individually associate with said key members and setby the operation thereof in position for locking the depressed key inthat position and engaging the steps of said bar upon the movement ofsaid unit for determining the extent of movement of the latter, a shafthaving a pinion engaging the gear sector of said unit, a pulsing camkeyed on said shaft, a pulsing contact, operable means associated withsaid cam for actuating said contact but normally positioned in a pathineife'ctive to actuate said contact upon the movement of said cam,means actuated by the movement of the operated key member for movingsaid operable means. in posimal position following the release of theoperated key by the operation of saidcombined stop and latch means bysaid unit.

8. In a call transmitter, a pulsing contact, a set ofkey members, a stepbar and gear sector 1- unit, a motor spring, a bar actuated by theoperation of any one of said key members for tensioning said motorspring. for operating said unit, a pawl for holding the depressed key inoperated position, an operable stop normally holding said i unit frommovement against the tension of said motor spring, a cam element carriedby said bar for actuating said stop to cause the operation of said unit,a pulsingfcam operably connected to".

the gear sector of said unit, a pawl-like member :1 actuated by said camfor actuating said contact.

said holding pawl having a cam portion'engaged by the step bar of saidunit to cause the release of the operated key, means carried by saidholding pawl for stopping the movement of said unit following therelease of the operated key, means for returning the operated key tonormal, means forreturning said unit to normal simultaneously with thereturn movement of the operated key, and a one-Way operable governormechanism actuated by the movement of said unit for controlling thespeed of said pulsing cam during the operation of said contact.

9. In a call transmitter, a motor spring, a of-digit key members, meansactuated by the operation of said key members for tensioning said motorspring, a step bar and gear sector unit actuated by the tension of saidmotor spring, a pulsing cam operatively connected to the gear sector ofsaid unit as effected by said motor spring, a contact, means actuated bysaid P1115? 13 ing cam for actuating said contact, a cam element carriedby each of said key members, means operable under control of the camelement carried by the depressed key for locking the latter to operatedposition during the operation of said cam, and means carried by the stepbar of said unit for operating said locking means for releasing theoperated key and stopping the operation of said unit for controlling theoperation of said pulsing cam.

10. In a call transmitter, a set of key members, a shaft, a helicalmotor spring coiled on said shaft, a movable step bar and gear sectorunit pivoted on said shaft, a motion amplifier lever mechanism, pivotedmeans on saidshaft actuated by the movement of any one of said keymembers for actuating said lever mechanism for imparting a greaterangular tensioning movement to said motor spring than the angularmovement imparted to said pivoted means on said shaft for operating saidunit, a pulsing mechanism actuated by the gear sector of said unit, andmeans movable upon the operation of the depressed key for locking thelatter in that position, said means cooperating with one step of saidstep bar for stopping the movement of said unit for controlling theoperation of said pulsing mechanism and releasing the operated key,

11. In a call transmitter, a pulsing mechanism, a set of longitudinallymovable digit key members, a pivoted bar, a step bar and gear sectorunit, a motor spring tensioned by the operation of said pivoted barunder control of any one of said key members for actuating said unit,operable means for holding said unit in normal position during thetensioning of said motor spring,

spring actuated pawls operable under control of means carried by saidkey members for individually holding the latter in operated position,means carried by said pivoted bar for moving said operable means inposition for releasing said unit following the tensioning of said motorspring, means actuated by said operable mean for collectively lockingthe non-operated key in that position simultaneously with the startingoperation of said unit for actuating said pulsing mechanism, meanscarried by the spring-operated pawl of the depressed key member forstopping the operation of said unit to a point corresponding to thevalue of the digit of the depressed key, means carried by the step barof said unit for moving the operated spring-operated pawl for releasingthe operated key, and a plurality of spring means for returning thedepressed key, said bar and said unitto normalv following the operationof's'aid pulsing mechanism. 7

12. In a call transmitter, a set of key members, a shaft, 3, bar pivotedon said shaft operable by the movement of any one of said key members, alever member actuated by the movement of said bar, an arm pivoted onsaid shaft actuated by said lever member, a Wedge element carried bysaid arm, a mounting for said key members, a bar secured to saidmounting, a pivot carried by said mounting, a lever member mounted forangular and longitudinal movement on said pivot, a roller mounted at thefree end of said lever member for engaging said wedge element and saidbar, a camming member pivoted on said mount ing for controlling theengagement of said roller with said wedge element and said bar, meanscarried by said wedge element for moving said camming member in positionfor holding said roller in position ineffective relative to said wedgeelement during the movement of one of said key members for normal tooperated position and to actuate said camming member to cause the ongagement of said roller with said wedge element and said bar forpreventing the redownward movement of the operated key member during thereturn movement of the latter from operated to full normal position, themeans carried by said wedge element operating said camming member formoving said roller in position ineffective relative to said wedgeelement upon the return of the depressed key to full operated position.

13. In a call transmitter, a set of key members,

a pivoted bar actuated by the movement of anyone of said key members,another bar disposed transverse of said key members formed withstaggered steps along its length and mounted for angular movementconcentric to said pivoted bar, a pawl-like member associated with eachof said key members and with each of said staggered steps in said otherbar for stopping the movement of the latter but normally in positionineffective relative to said other bar, a lever member actuated by saidpivoted bar, a motor spring tensioned by the movement of said levermember for actuating said step bar, means carried by said key members tocause the operation of said pawllike members in the path of theirrespective steps in said other bar and engaging means formed with saidkey members for locking them in the operated position, camming portionsformed with said pawl-like members engaged by their respective steps insaid other bar upon the movement of the latter under the tension of saidmotor spring. a pulsing mechanism, means carried by said other bar foractuating said pulsing mechanism, the movement of said bar, actuatingthe pawl-like member of the operated key for releasing the latterfollowing the operation of said pulsing mechanism.

14. In a call transmitter, a'set of digit numbered key members, apivoted bar actuated by the movement of any one of said key members,another bar movable concentric to the firstmentioned bar, said other barhaving a gear sector portion, motor means for actuating said other bar,a cam operatively connected to said gear sector, a pulsing contact,means operable upon the movement of said cam for actuating said contactbut normally positioned in a path where the operation of said cam isineffective to actuate said contact, means carried by said pivoted bar.

for moving the first-mentioned means in the path of said cam foractuating said contact upon the operation of said gear sector, springmeans for returning the operated key and said pivoted bar to normalposition following the operation of said contact, means set by themovement of the operated key member for stopping the movement of thelatter and said sector for transmitting a series of pulses correspondingto the digit of the operated key member, and spring means for returningthe-first-mentioned means to said in' effective path prior to the returnmovement of the operated key of said bar and or said gear sector tonormal position. I

15 'In'a call transmitter, a set of members,

a pivoted bar disposed for operation by the movement of any oneof saidkey members, a retractile spring for said bar, means "normallypositioned for engaging said pivotedbar for locking the latter'in thenon-operated position for col-1 lectively locking said key members innormal non-operated position, mean manuallyv operable mitting themovement of the latter by the individual movement of said key members,said first-mentioned meansbeing movable for per-- mitting the returnmovement of said bar to normal, under the tension of said retractilespring,

While said manually operable means is inthe operated position.

16. In a call transmitter, a set of rectangularly-shaped digit keymembers, a U-shaped bar, a shaft for pivotaliy supporting said U-shapedbar, a step bar pivotally supported by said shaft for angular movementconcentric to said U- shaped bar, another shaft disposed transverse. ofsaid key members, spring-pressed pawl-like members pivoted on thelast-mentioned shaft, one for each of said key members, cams carried bysaid key members forming ratchets for engagement with their respectivelyassociated pawllike members for individually locking said key members inthe operated position, said pawl-like members having projecting armsmovable in engageable relation with the steps of said bar upon thelocking of their respectively associated keys in the operated position,a third shaft disposedv transverse of said key members, a. plurality ofarms pivoted on said third shaft, one for each of said pawl-like membersoperativelyiconnected thereto, means carried by said arms forcontrolling the engagement of said pawl-like members with the teeth ofsaid key members, other means carried by said arms for stopping themovement of said step bar following the engagemerit of one of said stepswith the projectingarm of one of said pawl-like members for releasingits operated key, spring means for returning such a key to normalposition, the return movement of the operated key causing its cam toreturn its associated pawl-like member and its operatively connectingarm to normal, a gearing mechanism actuated. by the movement of saidstep bar, and a contact actuated by said mechanism a number of timescorresponding to the digit value of the depressed key. I

1'3. In a call transmitter, a pulsing mechanism,

a set of digit key members, a U-shaped bar actuated by the movement ofany one of said key members, a spring-operated means for locking thedepressed key to its operated position, a step bar gear sector unit, amotor spring tensioned by the movement of said U bar relative tosaidunit,

means for holding said step bar against movement d ring the tensioningof said motor spring,

a cam element carried by said U-chaped bar for actuating. said holdingmeans to cause the opera-.-

tion of said unit, means carried by said holding means for collectivelyengaging with means carried by the non-operated keys for locking thelatter in said non-operated position during the operation of said unitfor actuating said mechanism. l8.'A call transmitter comprising a set ofkey members, a pivoted bar actuated by the movement of any one of saidkey members, a step bar gear sector unit, a lever mechanism actuated,by,

said pivoted bar, a motor spring tensioned by said lever mechanism foractuating said unit, a pulsing mechanism driven by the gear sector ofsaid unit, means set by the movement of the operated Number 16 return ofthis key to full normal non-operated position.

19. In a call transmitter, a set of key members, a pivoted bar disposedfor operation by the movemerit of each of said key members, a gearsector, a pulsing mechanism keyed to said gear sector, an electric motorfor actuating said gear sector, a normally open contact in theenergizing circuit of said motor, a step bar movable as a unit with saidgear sector, operable means for normally holding said unit againstmovement during the operation of said pivoted bar, a cam carried by saidbar for actuating said operable means for permitting the -movement ofsaid unit, springactuated means positioned by the movement of theoperated key for closing said contact to cause theoperation of saidmotor, said spring-actuated means cooperating With one of the steps insaid step bar for reopening said contacts for stopping the operation ofsaid motor for determining the number of pulses transmitted by saidmechanism.

20. In a call transmitter, a set of manually operable key members, aretraotile spring for each of said key members, spring-actuated meansoperable upon the movement of any one of said key members for lockingthe latter in the operated position against the tension of itsretractile spring, a pivoted oar actuated by the movement of thedepressed key, another bar, means actuated by the movement of saidpivoted bar for actuating said other bar for engaging means carried bythis bar with means carried by said key member for collectively lookingthe nonoperated key members in that position, a pulsing mechanism, anelectric motor for actuating said mechanism, an energizing circuit forsaid motor having contacts closed by the individual operation of saidspring-actuated means for actuating said pulsing mechanism, meansactuated by said motor for moving the operated spring-actuated means inposition for releasing the operated key for permitting the returnmovement of the latter to normal position under the tension of itsretractile spring, and a Wedge mechanism operable.

upon the movement of said pivoted bar in position for stopping theoperated key upon an attempt to manually move this key towards operatedposition prior to the return of the latter to full non-operated positionfollowing the operation of said, pulsmg mechanism.

21. Ina call transmitter, a set of digit key members, a pulsing cam,amagnetic clutch, an electric motor, an energizing circuit connectingsaid magnetic clutch and said motor, said circuit having normally opencontacts, means operable upon the movement of any one of said key mem--bers for closing one of said contacts to cause the operation of saidmotor for actuating said pulsing cam, and a step bar actuated by saidmotor for REFERENCES CITED following references are of record in thefile of this patent: V

" UNITED sTATEs PATENTS Name Date 1.02.1,259 Neuhold Mar, 26, 19122,280,694

Richard Apr. 21, 1,942

may...

